Contextual effect on perception of lexical tones in Cantonese

The present study investigated the role of tonal context (extrinsic information) in the perception of Cantonese lexical tones. Target tones at three separate positions (initial, medial and final position) were recorded by two speakers (one male and one female). These sentences were edited and presented in three conditions: original carrier (target within the original context), isolation (target without context) and neutral carrier (target word as appended at the final apposition within a new carrier). Nine female listeners were asked to identify the tones by matching targets with Chinese characters. Perceptual data showed that tones presented within the original carrier were more accurately perceived than targets presented in isolation, showing the importance of extrinsic information in the perception of lexical tones. In the neutral carrier condition, tones of the final position showed perceptual accuracy significantly above targets of the initial and medial positions. The perceptual error patterns suggested that listeners placed more emphasis on the immediate context preceding the target in tone identification. When tones were presented without an extrinsic context, the proportion of errors for each tone differed. Most of the errors involved misidentifying targets as tones of same F0 contour but different level. The results showed that the importance of extrinsic information on the perception of lexical tones was mainly on identification of F0 level while the intrinsic acoustic properties of the tone helped in identifying the F0 contour.